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7 | |
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8 | <title>Copy Constructible</title> |
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9 | </head> |
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10 | |
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11 | <body bgcolor="#FFFFFF" link="#0000EE" text="#000000" vlink="#551A8B" alink= |
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12 | "#FF0000"> |
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13 | <img src="../../boost.png" alt="C++ Boost" width="277" height= |
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14 | "86"><br clear="none"> |
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15 | |
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16 | <h1>Copy Constructible</h1> |
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17 | |
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18 | <h3>Description</h3> |
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19 | |
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20 | <p>A type is Copy Constructible if it is possible to copy objects of that |
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21 | type.</p> |
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22 | |
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23 | <h3>Notation</h3> |
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24 | |
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25 | <table summary=""> |
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26 | <tr> |
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27 | <td valign="top"><tt>T</tt></td> |
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28 | |
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29 | <td valign="top">is type that is a model of Copy Constructible</td> |
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30 | </tr> |
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31 | |
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32 | <tr> |
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33 | <td valign="top"><tt>t</tt></td> |
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34 | |
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35 | <td valign="top">is an object of type <tt>T</tt></td> |
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36 | </tr> |
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37 | |
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38 | <tr> |
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39 | <td valign="top"><tt>u</tt></td> |
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40 | |
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41 | <td valign="top">is an object of type <tt>const T</tt></td> |
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42 | </tr> |
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43 | </table> |
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44 | |
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45 | <h3>Definitions</h3> |
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46 | |
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47 | <h3>Valid expressions</h3> |
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48 | |
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49 | <table border summary=""> |
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50 | <tr> |
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51 | <th>Name</th> |
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52 | |
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53 | <th>Expression</th> |
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54 | |
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55 | <th>Return type</th> |
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56 | |
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57 | <th>Semantics</th> |
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58 | </tr> |
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59 | |
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60 | <tr> |
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61 | <td valign="top">Copy constructor</td> |
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62 | |
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63 | <td valign="top"><tt>T(t)</tt></td> |
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64 | |
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65 | <td valign="top"><tt>T</tt></td> |
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66 | |
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67 | <td valign="top"><tt>t</tt> is equivalent to <tt>T(t)</tt></td> |
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68 | </tr> |
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69 | |
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70 | <tr> |
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71 | <td valign="top">Copy constructor</td> |
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72 | |
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73 | <td valign="top"> |
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74 | <pre> |
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75 | T(u) |
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76 | </pre> |
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77 | </td> |
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78 | |
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79 | <td valign="top"><tt>T</tt></td> |
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80 | |
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81 | <td valign="top"><tt>u</tt> is equivalent to <tt>T(u)</tt></td> |
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82 | </tr> |
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83 | |
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84 | <tr> |
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85 | <td valign="top">Destructor</td> |
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86 | |
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87 | <td valign="top"> |
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88 | <pre> |
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89 | t.~T() |
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90 | </pre> |
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91 | </td> |
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92 | |
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93 | <td valign="top"><tt>T</tt></td> |
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94 | |
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95 | <td valign="top"> </td> |
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96 | </tr> |
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97 | |
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98 | <tr> |
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99 | <td valign="top">Address Operator</td> |
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100 | |
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101 | <td valign="top"> |
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102 | <pre> |
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103 | &t |
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104 | </pre> |
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105 | </td> |
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106 | |
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107 | <td valign="top"><tt>T*</tt></td> |
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108 | |
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109 | <td valign="top">denotes the address of <tt>t</tt></td> |
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110 | </tr> |
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111 | |
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112 | <tr> |
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113 | <td valign="top">Address Operator</td> |
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114 | |
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115 | <td valign="top"> |
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116 | <pre> |
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117 | &u |
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118 | </pre> |
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119 | </td> |
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120 | |
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121 | <td valign="top"><tt>T*</tt></td> |
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122 | |
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123 | <td valign="top">denotes the address of <tt>u</tt></td> |
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124 | </tr> |
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125 | </table> |
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126 | |
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127 | <h3>Models</h3> |
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128 | |
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129 | <ul> |
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130 | <li><tt>int</tt></li> |
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131 | |
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132 | <li><tt>std::pair</tt></li> |
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133 | </ul> |
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134 | |
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135 | <h3>Concept Checking Class</h3> |
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136 | <pre> |
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137 | template <class T> |
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138 | struct CopyConstructibleConcept |
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139 | { |
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140 | void constraints() { |
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141 | T a(b); // require copy constructor |
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142 | T* ptr = &a; // require address of operator |
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143 | const_constraints(a); |
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144 | ignore_unused_variable_warning(ptr); |
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145 | } |
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146 | void const_constraints(const T& a) { |
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147 | T c(a); // require const copy constructor |
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148 | const T* ptr = &a; // require const address of operator |
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149 | ignore_unused_variable_warning(c); |
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150 | ignore_unused_variable_warning(ptr); |
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151 | } |
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152 | T b; |
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153 | }; |
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154 | </pre> |
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155 | |
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156 | <h3>See also</h3> |
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157 | |
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158 | <p><a href="http://www.sgi.com/tech/stl/DefaultConstructible.html">Default |
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159 | Constructible</a> and <a href="./Assignable.html">Assignable</a><br></p> |
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160 | <hr> |
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161 | |
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162 | <p><a href="http://validator.w3.org/check?uri=referer"><img border="0" src= |
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163 | "http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01 Transitional" |
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164 | height="31" width="88"></a></p> |
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165 | |
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166 | <p>Revised |
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167 | <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->05 |
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168 | December, 2006<!--webbot bot="Timestamp" endspan i-checksum="38516" --></p> |
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169 | |
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170 | <table summary=""> |
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171 | <tr valign="top"> |
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172 | <td nowrap><i>Copyright © 2000</i></td> |
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173 | |
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174 | <td><i><a href="http://www.lsc.nd.edu/~jsiek">Jeremy Siek</a>, Univ.of |
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175 | Notre Dame (<a href= |
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176 | "mailto:jsiek@lsc.nd.edu">jsiek@lsc.nd.edu</a>)</i></td> |
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177 | </tr> |
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178 | </table> |
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179 | |
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180 | <p><i>Distributed under the Boost Software License, Version 1.0. (See |
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181 | accompanying file <a href="../../LICENSE_1_0.txt">LICENSE_1_0.txt</a> or |
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182 | copy at <a href= |
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183 | "http://www.boost.org/LICENSE_1_0.txt">http://www.boost.org/LICENSE_1_0.txt</a>)</i></p> |
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184 | </body> |
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185 | </html> |
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